Stereoselective functionalisation of cis- and trans-2-ferrocenyl-3-pivaloyl-4-alkyl-1,3-oxazolidin-5-ones: asymmetric synthesis of (R)- and (S)-2-alkyl-2-aminopent-4-enoic acids and (2R,3S)-2-amino-2-methyl-3-hydroxy-3-phenylpropanoic acid.
Org Biomol Chem
; 7(3): 527-36, 2009 Feb 07.
Article
en En
| MEDLINE
| ID: mdl-19156319
Treatment of a range of cis- and trans-2-ferrocenyl-3-pivaloyl-4-alkyl-1,3-oxazolidin-5-ones with LDA followed by the addition of allyl bromide promotes highly stereoselective allylation (>98% de) at the 4-position of the oxazolidinone ring anti to the stereodirecting 2-ferrocenyl group. Hydrolysis of the resultant 4,4-disubstituted oxazolidinones (>98% de) yields enantiomeric (R)- and (S)-2-alkyl-2-aminopent-4-enoic acids in high ee. Furthermore, the aldol reaction of the lithium enolate of cis-2-ferrocenyl-3-pivaloyl-4-methyl-1,3-oxazolidin-5-one with benzaldehyde followed by in situ O-protection affords O-protected aldol products in >98% de, with hydrolysis affording (2R,3S)-2-amino-2-methyl-3-hydroxy-3-phenylpropanoic acid in >98% de.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Fenilpropionatos
/
Oxazolidinonas
/
Alilglicina
Idioma:
En
Revista:
Org Biomol Chem
Asunto de la revista:
BIOQUIMICA
/
QUIMICA
Año:
2009
Tipo del documento:
Article
Pais de publicación:
Reino Unido